Thanks so much for all your ideas!! The tire in question is a 26" x 1.35" Marathon Plus - it just seemed like it was too small for the rim. We're hoping he doesn't get a flat in it!

We've been running the Marathon Plus on my bike and my husband's all the way down from Alaska. At this point, we've got nearly 6000 miles on the bikes, and I've had two flats in my 700c tire - both from pieces of glass that worked their way in. John has gotten three flats in his 26" - I"m not sure from what.

Thetires Davy has been using are the Specialized Armadillos, but he's been getting soooo many flats lately that we decided to swap his tire out for the Schwalbe. We're keeping his old tire for once we are out of thorn country, but right now it got to the point where it was ridiculous - he was getting 1 - 2 flats/day!!